Obviously you are not clear with your point yeah so if you are holding an altcoin and you see updates on Twitter and the rest of the social media and that shows decline in the price movement and you begin to fear then what you need to do is do more research more concerning that particular coin, search for groups where holders of the same coin communicate or share idea.

Then you will find updates on what and what not to do at the moment because currently, here we do not know what situation you are in or what coin you are talking about but if it is something like Bitcoin which you obviously stated you are in for a long time hence I will advise you keep Holding but if it is an altcoin which I am not certain about it volatility then I would suggest you make more research concerning that particular coin in order not to loss everything.